Video: Ukrainian forces hoist flag in area 'recaptured' from Russia

The Ukrainian Armed Forces shared a video on Sunday showing a soldier hoisting the country's flag above a Kharkiv region settlement which it says was recently taken back from Russian forces.

Re-shared by numerous official accounts and outlets, including by President Volodymyr Zelenskyy, the video purports to show a soldier of the 14 Separate Mechanized Brigade declaring the town of Chkalovske liberated from Russians.

Ukrainian forces on Sunday pushed its counteroffensive in the country's east, exploiting quick gains they made in a week of fighting that has sharply changed the course of the conflict.

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Ukraine's quick action to reclaim Russia-occupied areas in the northeastern Kharkiv region forced Moscow to withdraw its troops to prevent them from being surrounded and leave behind significant numbers of weapons and munitions in a hasty retreat as the war marked 200 days on Sunday.

The jubilant Zelenskyy mocked the Russians in a video address late Saturday, saying that "the Russian army in these days is demonstrating the best that it can do — showing its back."

The Russian pullback marked the biggest battlefield success for Ukrainian forces since they thwarted a Russian attempt to seize the capital, Kyiv, at the start of the nearly seven-month war.